An embedded system is a “dedicated computerized system designed for specific applications that is entirely embedded in a controlled device”. The embedded system serves to control, monitor or assist in devices, machines or facilities in plants. Unlike a general-purpose computer system such as PCs, an embedded system usually executes predefined tasks with specific requirements. Embedded systems are used to control or monitor large-scale equipment such as machines, facilities and plants. In general, an embedded system is an embedded processor control board whose control program is stored in a ROM. In fact, all devices with digital interfaces such as watches, microwaves, video records, cars, etc. use embedded systems. Some embedded systems even include an OS, but most embedded systems realize entire logic control through a single program.
The combination of embedded technology with video coding technology and network communication technology can realize the embedded video surveillance system, Video surveillance is widely used in a variety of other fields such as daily life, corporate management, security, border control and so on, for example: 1. Video surveillance system brings convenience to production. Most basically, video surveillance can replace human monitoring and control in some harsh environments, such a system is in small size with stable performance and can ensure safety as well. In addition, video surveillance does not have physical defects of humans such as visual fatigue, hence ensuring production safety under normal circumstances. 2. Video surveillance brings convenience to life. For example, video surveillance in traffic monitoring features timeliness, accuracy and wide monitoring range, and can notify the traffic police and solve problems at the first time in the event of traffic congestions and accidents. 3. Video surveillance ensures security. The system can be installed in supermarkets, banks, plants, construction sites and other places, to learn about indoor situations, customer behaviors, etc. This can effectively guarantee the rights and interests of bank card holders, monitor the operations of the plant, and improve the social security and safety level. 4. Militarily, video surveillance can be used in military intelligence survey and target tracking. So, video surveillance can bring convenience to all kinds of fields. Meanwhile, data of surveillance videos are also very important.
Especially, when there are abnormal incidents caused by human in life, security and military scenarios, monitoring data can record situations at the time such that people can understand what happened back then. However, when the embedded system runs continuously for a long time, the machine may become erroneous and monitoring data will not be recognized by the embedded system, or the data may be tempered with and therefore cannot be recognized by the system. In such a case, the abnormal incident cannot be reproduced. As a result, research on the predefinition format of the embedded system is of special importance.
Digital Video Recorders (DVRs) that store video data in their hard disks have already replaced analog video recorders. DVRs include PC-DVRs based on PC architecture and embedded DVRs independent from PC architecture. It is a computing system that can independently store and process images with functions including long-time video recording, audio recording, and remote monitoring and control over images and voice. However, the deletion and overwriting of videos for various reasons may easily cause data loss.
Residual and deleted videos cannot be extracted presently and the extraction of data stored in a DVR hard disk may suffer incompatibility as different manufacturers and various types of hard disks will lead to different video stream headers. The present invention will analyze data generated by the firmware algorithm in the wave-particle monitoring, so as to complete the algorithm for data extraction.